/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

/// <reference path="../../../typings/require.d.ts" />

//@ts-check
(function () {
	'use strict';

	/**
	 * @param {NodeRequire} nodeRequire
	 * @param {typeof import('path')} path
	 * @param {typeof import('fs')} fs
	 * @param {typeof import('../common/performance')} perf
	 */
	function factory(nodeRequire, path, fs, perf) {

		/**
		 * @param {string} file
		 * @returns {Promise<boolean>}
		 */
		function exists(file) {
			return new Promise(c => fs.exists(file, c));
		}

		/**
		 * @param {string} file
		 * @returns {Promise<void>}
		 */
		function touch(file) {
			return new Promise((c, e) => { const d = new Date(); fs.utimes(file, d, d, err => err ? e(err) : c()); });
		}

		/**
		 * @param {string} dir
		 * @returns {Promise<string>}
		 */
		function mkdirp(dir) {
			return new Promise((c, e) => fs.mkdir(dir, { recursive: true }, err => (err && err.code !== 'EEXIST') ? e(err) : c(dir)));
		}

		/**
		 * @param {string} location
		 * @returns {Promise<void>}
		 */
		function rimraf(location) {
			return new Promise((c, e) => fs.rmdir(location, { recursive: true }, err => (err && err.code !== 'ENOENT') ? e(err) : c()));
		}

		/**
		 * @param {string} file
		 * @returns {Promise<string>}
		 */
		function readFile(file) {
			return new Promise((c, e) => fs.readFile(file, 'utf8', (err, data) => err ? e(err) : c(data)));
		}

		/**
		 * @param {string} file
		 * @param {string} content
		 * @returns {Promise<void>}
		 */
		function writeFile(file, content) {
			return new Promise((c, e) => fs.writeFile(file, content, 'utf8', err => err ? e(err) : c()));
		}

		/**
		 * @param {string} userDataPath
		 * @returns {object}
		 */
		function getLanguagePackConfigurations(userDataPath) {
			const configFile = path.join(userDataPath, 'languagepacks.json');
			try {
				return nodeRequire(configFile);
			} catch (err) {
				// Do nothing. If we can't read the file we have no
				// language pack config.
			}
			return undefined;
		}

		/**
		 * @param {object} config
		 * @param {string} locale
		 */
		function resolveLanguagePackLocale(config, locale) {
			try {
				while (locale) {
					if (config[locale]) {
						return locale;
					} else {
						const index = locale.lastIndexOf('-');
						if (index > 0) {
							locale = locale.substring(0, index);
						} else {
							return undefined;
						}
					}
				}
			} catch (err) {
				console.error('Resolving language pack configuration failed.', err);
			}
			return undefined;
		}

		/**
		 * @param {string} commit
		 * @param {string} userDataPath
		 * @param {string} metaDataFile
		 * @param {string} locale
		 */
		function getNLSConfiguration(commit, userDataPath, metaDataFile, locale) {
			if (locale === 'pseudo') {
				return Promise.resolve({ locale: locale, availableLanguages: {}, pseudo: true });
			}

			if (process.env['VSCODE_DEV']) {
				return Promise.resolve({ locale: locale, availableLanguages: {} });
			}

			// We have a built version so we have extracted nls file. Try to find
			// the right file to use.

			// Check if we have an English or English US locale. If so fall to default since that is our
			// English translation (we don't ship *.nls.en.json files)
			if (locale && (locale === 'en' || locale === 'en-us')) {
				return Promise.resolve({ locale: locale, availableLanguages: {} });
			}

			const initialLocale = locale;

			perf.mark('code/willGenerateNls');

			const defaultResult = function (locale) {
				perf.mark('code/didGenerateNls');
				return Promise.resolve({ locale: locale, availableLanguages: {} });
			};
			try {
				if (!commit) {
					return defaultResult(initialLocale);
				}
				const configs = getLanguagePackConfigurations(userDataPath);
				if (!configs) {
					return defaultResult(initialLocale);
				}
				locale = resolveLanguagePackLocale(configs, locale);
				if (!locale) {
					return defaultResult(initialLocale);
				}
				const packConfig = configs[locale];
				let mainPack;
				if (!packConfig || typeof packConfig.hash !== 'string' || !packConfig.translations || typeof (mainPack = packConfig.translations['vscode']) !== 'string') {
					return defaultResult(initialLocale);
				}
				return exists(mainPack).then(fileExists => {
					if (!fileExists) {
						return defaultResult(initialLocale);
					}
					const packId = packConfig.hash + '.' + locale;
					const cacheRoot = path.join(userDataPath, 'clp', packId);
					const coreLocation = path.join(cacheRoot, commit);
					const translationsConfigFile = path.join(cacheRoot, 'tcf.json');
					const corruptedFile = path.join(cacheRoot, 'corrupted.info');
					const result = {
						locale: initialLocale,
						availableLanguages: { '*': locale },
						_languagePackId: packId,
						_translationsConfigFile: translationsConfigFile,
						_cacheRoot: cacheRoot,
						_resolvedLanguagePackCoreLocation: coreLocation,
						_corruptedFile: corruptedFile
					};
					return exists(corruptedFile).then(corrupted => {
						// The nls cache directory is corrupted.
						let toDelete;
						if (corrupted) {
							toDelete = rimraf(cacheRoot);
						} else {
							toDelete = Promise.resolve(undefined);
						}
						return toDelete.then(() => {
							return exists(coreLocation).then(fileExists => {
								if (fileExists) {
									// We don't wait for this. No big harm if we can't touch
									touch(coreLocation).catch(() => { });
									perf.mark('code/didGenerateNls');
									return result;
								}
								return mkdirp(coreLocation).then(() => {
									return Promise.all([readFile(metaDataFile), readFile(mainPack)]);
								}).then(values => {
									const metadata = JSON.parse(values[0]);
									const packData = JSON.parse(values[1]).contents;
									const bundles = Object.keys(metadata.bundles);
									const writes = [];
									for (const bundle of bundles) {
										const modules = metadata.bundles[bundle];
										const target = Object.create(null);
										for (const module of modules) {
											const keys = metadata.keys[module];
											const defaultMessages = metadata.messages[module];
											const translations = packData[module];
											let targetStrings;
											if (translations) {
												targetStrings = [];
												for (let i = 0; i < keys.length; i++) {
													const elem = keys[i];
													const key = typeof elem === 'string' ? elem : elem.key;
													let translatedMessage = translations[key];
													if (translatedMessage === undefined) {
														translatedMessage = defaultMessages[i];
													}
													targetStrings.push(translatedMessage);
												}
											} else {
												targetStrings = defaultMessages;
											}
											target[module] = targetStrings;
										}
										writes.push(writeFile(path.join(coreLocation, bundle.replace(/\//g, '!') + '.nls.json'), JSON.stringify(target)));
									}
									writes.push(writeFile(translationsConfigFile, JSON.stringify(packConfig.translations)));
									return Promise.all(writes);
								}).then(() => {
									perf.mark('code/didGenerateNls');
									return result;
								}).catch(err => {
									console.error('Generating translation files failed.', err);
									return defaultResult(locale);
								});
							});
						});
					});
				});
			} catch (err) {
				console.error('Generating translation files failed.', err);
				return defaultResult(locale);
			}
		}

		return {
			getNLSConfiguration
		};
	}

	if (typeof define === 'function') {
		// amd
		define(['require', 'path', 'fs', 'vs/base/common/performance'], function (require, /** @type {typeof import('path')} */ path, /** @type {typeof import('fs')} */ fs, /** @type {typeof import('../common/performance')} */ perf) { return factory(require.__$__nodeRequire, path, fs, perf); });
	} else if (typeof module === 'object' && typeof module.exports === 'object') {
		const path = require('path');
		const fs = require('fs');
		const perf = require('../common/performance');
		module.exports = factory(require, path, fs, perf);
	} else {
		throw new Error('Unknown context');
	}
}());
